In keeping with its “green” efforts, the Mansion House recently installed a new system that utilizes heat generated by the air-conditioning system to heat the swimming pool. It ties in with a project a few years ago to install a geothermal heat pump system in the hotel, run by the stored solar energy found in the abundant groundwater below the building, along with a sophisticated energy control system.

The pool, which was still heated by fuel-oil fired boilers, was discovered to be losing heat because of the cooler groundwater that runs beneath it. Hotel plant engineer Jay McMann and electrician Dana Thornton suggested tapping wasted heat from the air-conditioning load to heat the pool.

In December 2012, Nelson Mechanical Design (NMD) installed a large heat exchanger in the hotel’s basement. It now pulls heat out of the inside geothermal building loop, generated at least 10 months of the year by all of the hotel’s heat pumps, to heat the swimming pool, according to NMD owner Brian Nelson.

Josh Goldstein, whose family owns the Mansion House, said last week the hotel has already saved 600 gallons of fuel oil since the new system’s installation and expects to save $13,000 a year in fuel oil costs over its projected 20-year lifespan.

Mr. Goldstein said the hotel is moving forward on a project to install another heat exchanger to utilize additional energy from the building’s inside geothermal loop that will preheat the building’s hot water.